---
id: CVE-2026-33244
aliases:
  - GHSA-f22v-gfqf-p8f3
title: >-
  React Router has stored XSS via unescaped Location header in prerendered
  redirect HTML
summary: >-
  React Router has stored XSS via unescaped Location header in prerendered
  redirect HTML
severity: medium
cvss: 5.4
cwe:
  - CWE-79
vendor: react-router
product: react-router
ecosystem: npm
affected:
  - 'react-router >= 7.5.1, < 7.13.2'
patched:
  - react-router 7.13.2
published: '2026-06-03'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T16:28:03Z'
source: GHSA
sourceUrl: 'https://github.com/advisories/GHSA-f22v-gfqf-p8f3'
references:
  - url: >-
      https://github.com/remix-run/react-router/security/advisories/GHSA-f22v-gfqf-p8f3
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-33244'
  - url: 'https://github.com/remix-run/react-router/pull/14880'
  - url: >-
      https://github.com/remix-run/react-router/commit/ea28e66926460656815cee9b7f2dfaa872513a8c
  - url: >-
      https://github.com/remix-run/react-router/blob/react-router%407.13.2/CHANGELOG.md#v7132
  - url: 'https://github.com/advisories/GHSA-f22v-gfqf-p8f3'
tags:
  - ghsa
  - npm
epss: 0.00231
epssPercentile: 0.12459
ingestedAt: '2026-09-08T17:06:31.882Z'
---

## Overview

When using React Router v7 [Framework Mode](https://reactrouter.com/start/modes#framework) with [Pre-rendering](https://reactrouter.com/how-to/pre-rendering) enabled, an improper neutralization of the HTTP `Location` header value can permit Cross-Site Scripting (XSS) in statically generated HTML files if the redirect location comes from an untrusted source.

> [!NOTE]
> This does not impact your React Router application if you are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`<BrowserRouter>`) or [Data Mode](https://reactrouter.com/start/modes#data) (`createBrowserRouter`/`<RouterProvider>`).

## Affected packages

- `react-router >= 7.5.1, < 7.13.2`

## Remediation

Upgrade to a patched release:

- `react-router 7.13.2`